user/sven/linux.git/include/linux/sbitmap.h, branch v5.15.26

scsi: sbitmap: Silence a debug kernel warning triggered by sbitmap_put()

2021-03-19T02:39:30Z

All sbitmap code uses implied preemption protection to update sb->alloc_hint except sbitmap_put(). Using implied preemption protection is safe since the value of sb->alloc_hint only affects performance of sbitmap allocations but not their correctness. Change this_cpu_ptr() in sbitmap_put() into raw_cpu_ptr() to suppress the following kernel warning that appears with preemption debugging enabled (CONFIG_DEBUG_PREEMPT): BUG: using smp_processor_id() in preemptible [00000000] code: scsi_eh_0/152 caller is debug_smp_processor_id+0x17/0x20 CPU: 1 PID: 152 Comm: scsi_eh_0 Tainted: G W 5.12.0-rc1-dbg+ #6 Call Trace: show_stack+0x52/0x58 dump_stack+0xaf/0xf3 check_preemption_disabled+0xce/0xd0 debug_smp_processor_id+0x17/0x20 scsi_device_unbusy+0x13a/0x1c0 [scsi_mod] scsi_finish_command+0x4d/0x290 [scsi_mod] scsi_eh_flush_done_q+0x1e7/0x280 [scsi_mod] ata_scsi_port_error_handler+0x592/0x750 [libata] ata_scsi_error+0x1a0/0x1f0 [libata] scsi_error_handler+0x19e/0x330 [scsi_mod] kthread+0x222/0x250 ret_from_fork+0x1f/0x30 Link: https://lore.kernel.org/r/20210317032648.9080-1-bvanassche@acm.org Fixes: c548e62bcf6a ("scsi: sbitmap: Move allocation hint into sbitmap") Cc: Hannes Reinecke Cc: Omar Sandoval Reviewed-by: Ming Lei Reviewed-by: Christoph Hellwig Signed-off-by: Bart Van Assche Signed-off-by: Martin K. Petersen

scsi: sbitmap: Add sbitmap_calculate_shift() helper

2021-03-04T22:36:59Z

Move code for calculating default shift into a public helper which can be used by SCSI. Link: https://lore.kernel.org/r/20210122023317.687987-7-ming.lei@redhat.com Cc: Omar Sandoval Cc: Kashyap Desai Cc: Sumanesh Samanta Cc: Ewan D. Milne Tested-by: Sumanesh Samanta Reviewed-by: Hannes Reinecke Signed-off-by: Ming Lei Signed-off-by: Martin K. Petersen

scsi: sbitmap: Export sbitmap_weight

2021-03-04T22:36:59Z

SCSI's .device_busy will be converted to sbitmap and sbitmap_weight is needed. Export the helper. The only existing user of sbitmap_weight() uses it to find out how many bits are set and not cleared. Align sbitmap_weight() meaning with this usage model. Link: https://lore.kernel.org/r/20210122023317.687987-6-ming.lei@redhat.com Cc: Omar Sandoval Cc: Kashyap Desai Cc: Sumanesh Samanta Cc: Ewan D. Milne Tested-by: Sumanesh Samanta Reviewed-by: Hannes Reinecke Signed-off-by: Ming Lei Signed-off-by: Martin K. Petersen

scsi: sbitmap: Move allocation hint into sbitmap

2021-03-04T22:36:59Z

Allocation hint should have belonged to sbitmap. Also, when sbitmap's depth is high and there is no need to use mulitple wakeup queues, user can benefit from percpu allocation hint too. Move allocation hint into sbitmap, then SCSI device queue can benefit from allocation hint when converting to plain sbitmap. Convert vhost/scsi.c to use sbitmap allocation with percpu alloc hint. This is more efficient than the previous approach. Link: https://lore.kernel.org/r/20210122023317.687987-5-ming.lei@redhat.com Cc: Omar Sandoval Cc: Kashyap Desai Cc: Sumanesh Samanta Cc: Ewan D. Milne Cc: Mike Christie Cc: virtualization@lists.linux-foundation.org Tested-by: Sumanesh Samanta Reviewed-by: Hannes Reinecke Signed-off-by: Ming Lei Signed-off-by: Martin K. Petersen

scsi: sbitmap: Maintain allocation round_robin in sbitmap

2021-03-04T22:36:59Z

Currently the allocation round_robin info is maintained by sbitmap_queue. However, bit allocation really belongs to sbitmap. Move it there. Link: https://lore.kernel.org/r/20210122023317.687987-3-ming.lei@redhat.com Cc: Omar Sandoval Cc: Kashyap Desai Cc: Sumanesh Samanta Cc: Ewan D. Milne Cc: Hannes Reinecke Cc: virtualization@lists.linux-foundation.org Tested-by: Sumanesh Samanta Reviewed-by: Hannes Reinecke Signed-off-by: Ming Lei Signed-off-by: Martin K. Petersen

scsi: sbitmap: Remove sbitmap_clear_bit_unlock

2021-03-04T22:36:59Z

No one uses this helper any more, so kill it. Link: https://lore.kernel.org/r/20210122023317.687987-2-ming.lei@redhat.com Cc: Omar Sandoval Cc: Kashyap Desai Cc: Sumanesh Samanta Cc: Ewan D. Milne Cc: Hannes Reinecke Tested-by: Sumanesh Samanta Reviewed-by: Hannes Reinecke Reviewed-by: Johannes Thumshirn Signed-off-by: Ming Lei Signed-off-by: Martin K. Petersen

sbitmap: remove swap_lock

2020-12-08T00:12:49Z

map->swap_lock protects map->cleared from concurrent modification, however sbitmap_deferred_clear() is already atomically drains it, so it's guaranteed to not loose bits on concurrent sbitmap_deferred_clear(). A one threaded tag heavy test on top of nullbk showed ~1.5% t-put increase, and 3% -> 1% cycle reduction of sbitmap_get() according to perf. Signed-off-by: Pavel Begunkov Signed-off-by: Jens Axboe

sbitmap: Delete sbitmap_any_bit_clear()

2019-11-13T19:50:40Z

Since the only caller of this function has been deleted, delete this one also. Signed-off-by: John Garry Signed-off-by: Jens Axboe

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 328

2019-06-05T15:37:06Z

Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license v2 as published by the free software foundation this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not see https www gnu org licenses extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 2 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Alexios Zavras Reviewed-by: Armijn Hemel Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190530000435.923873561@linutronix.de Signed-off-by: Greg Kroah-Hartman

sbitmap: trivial - update comment for sbitmap_deferred_clear_bit

2019-03-22T17:01:02Z

"sbitmap_batch_clear" should be "sbitmap_deferred_clear" Acked-by: Omar Sandoval Signed-off-by: Shenghui Wang Signed-off-by: Jens Axboe